A5064909614- Quantum Computing Algorithms and Architecture
- Quantum Information and Cryptography
- Quantum and electron transport phenomena
- Quantum-Dot Cellular Automata
- Quantum Mechanics and Applications
- Advancements in Semiconductor Devices and Circuit Design
- Parallel Computing and Optimization Techniques
- Computability, Logic, AI Algorithms
- Advanced Data Storage Technologies
- Low-power high-performance VLSI design
- History and Developments in Astronomy
- Cloud Computing and Resource Management
- Logic, programming, and type systems
- Photonic and Optical Devices
- Gyrotron and Vacuum Electronics Research
- Machine Learning and Algorithms
- Particle accelerators and beam dynamics
- Plasma Diagnostics and Applications
- Ferroelectric and Negative Capacitance Devices
- Error Correcting Code Techniques
- Geochemistry and Geologic Mapping
- Advanced Optimization Algorithms Research
- Cryptographic Implementations and Security
- Numerical Methods and Algorithms
- Mathematical functions and polynomials
IBM (United States)
2013-2025
IBM Research - Thomas J. Watson Research Center
2009-2024
GE Global Research (United States)
2021
Massachusetts Institute of Technology
2003-2011
MIT-Harvard Center for Ultracold Atoms
2011
Science Applications International Corporation (United States)
2011
Ohio Aerospace Institute
2003
Glenn Research Center
2003
Universal fault-tolerant quantum computers will require error-free execution of long sequences gate operations, which is expected to involve millions physical qubits. Before the full power such machines be available, near-term devices provide several hundred qubits and limited error correction. Still, there a realistic prospect run useful algorithms within circuit depth devices. Particularly promising are optimization that follow hybrid approach: aim steer highly entangled state on system...
We introduce a single-number metric, quantum volume, that can be measured using concrete protocol on near-term computers of modest size ($n\ensuremath{\lesssim}50$), and measure it several state-of-the-art transmon devices, finding values as high 16. The volume is linked to system error rates, empirically reduced by uncontrolled interactions within the system. It quantifies largest random circuit equal width depth computer successfully implements. Quantum computing systems with high-fidelity...
To build a fault-tolerant quantum computer, it is necessary to implement error correcting code. Such codes rely on the ability extract information about syndrome while not destroying encoded in system. Stabilizer are attractive solutions this problem, as they analogous classical linear codes, have simple and easily computed encoding networks, allow efficient extraction. In these extraction performed via multi-qubit stabilizer measurements, which bit phase parity checks up local operations....
This document describes a quantum assembly language (QASM) called OpenQASM that is used to implement experiments with low depth circuits. represents universal physical circuits over the CNOT plus SU(2) basis straight-line code includes measurement, reset, fast feedback, and gate subroutines. The simple text can be written by hand or higher level tools may executed on IBM Q Experience.
Robust quantum computation requires encoding delicate information into degrees of freedom that are hard for the environment to change. Quantum encodings have been demonstrated in many physical systems by observing and correcting storage errors, but applications require not just storing information; we must accurately compute even with faulty operations. The theory fault-tolerant computing illuminates a way forward providing foundation collection techniques limiting spread errors. Here...
In this work we introduce two code families, which call the heavy hexagon and square code. Both families are implemented by assigning physical data ancilla qubits to both vertices edges of low degree graphs. Such a layout is particularly suitable for superconducting qubit architectures minimize frequency collisions crosstalk. some cases, can be reduced several orders magnitude. The hybrid surface/Bacon-Shor mapped onto (heavy) hexagonal lattice whereas surface lattice. includes all required...
We present parity measurements on a five-qubit lattice with connectivity amenable to the surface code quantum error correction architecture. Using all-microwave controls of superconducting qubits coupled via resonators, we encode parities four data qubit states in either X or Z basis. Given lattice, perform full characterization static interactions within set five qubits, as well dynamical brought along by single- and two-qubit microwave drives. The are significantly improved modifying gates...
The concept of quantum computing has inspired a whole new generation scientists, including physicists, engineers, and computer to fundamentally change the landscape information technology. With experimental demonstrations stretching back more than two decades, community achieved major milestone over past few years: ability build systems that are limits what can be classically simulated, which enable cloud-based research for wide range thus increasing pool talent exploring early systems....
Quantum assembly languages are machine-independent that traditionally describe quantum computation in the circuit model. Open language (OpenQASM 2) was proposed as an imperative programming for circuits based on earlier QASM dialects. In principle, any could be described using OpenQASM 2, but there is a need to broader set of beyond qubits and gates. By examining interactive use cases, we recognize two different timescales quantum-classical interactions: real-time classical computations must...
Abstract The accumulation of physical errors 1–3 prevents the execution large-scale algorithms in current quantum computers. Quantum error correction 4 promises a solution by encoding k logical qubits onto larger number n qubits, such that are suppressed enough to allow running desired computation with tolerable fidelity. becomes practically realizable once rate is below threshold value depends on choice code, syndrome measurement circuit and decoding algorithm 5 . We present an end-to-end...
Quantum error correction offers a promising path for performing high fidelity quantum computations. Although fully fault-tolerant executions of algorithms remain unrealized, recent improvements in control electronics and hardware enable increasingly advanced demonstrations the necessary operations correction. Here, we perform on superconducting qubits connected heavy-hexagon lattice. We encode logical qubit with distance three several rounds syndrome measurements that allow any single fault...
We describe Qiskit, a software development kit for quantum information science. discuss the key design decisions that have shaped its development, and examine architecture core components. demonstrate an end-to-end workflow solving problem in condensed matter physics on computer serves to highlight some of Qiskit's capabilities, example representation optimization circuits at various abstraction levels, scalability retargetability new gates, use quantum-classical computations via dynamic...
Abstract To run large-scale algorithms on a quantum computer, error-correcting codes must be able to perform fundamental set of operations, called logic gates, while isolating the encoded information from noise 1–8 . We can complete universal gates by producing special resources magic states 9–11 It is therefore important produce high-fidelity conduct introducing minimal amount computation. Here we propose and implement scheme prepare state superconducting qubit array using error correction....
We discuss how the presence of gauge subsystems in Bacon-Shor code [D. Bacon, Phys. Rev. A 73, 012340 (2006)10.1103/PhysRevA.73.012340 (2006)] leads to remarkably simple and efficient methods for fault-tolerant error correction (FTEC). Most notably, FTEC does not require entangled ancillary states, it can be implemented with nearest-neighbor two-qubit measurements. By using these methods, we prove a lower bound on quantum accuracy threshold, 1.94 x 10(-4) adversarial stochastic noise, that...
Abstract The main promise of quantum computing is to efficiently solve certain problems that are prohibitively expensive for a classical computer. Most with proven advantage involve the repeated use black box, or oracle, whose structure encodes solution. One measure algorithmic performance query complexity, i.e., scaling number oracle calls needed find solution given probability. Few-qubit demonstrations algorithms, such as Deutsch–Jozsa and Grover, have been implemented across diverse...
In this paper, we analyze the performance of randomized benchmarking protocols on gate sets under a variety realistic error models that include systematic rotations, amplitude damping, leakage to higher levels, and 1/f noise. We find that, in almost all cases, provides better than factor-of-two estimate average rate, suggesting are valuable tool for verification validation quantum operations. addition, derive new fidelity decay curves certain types non-Markovian noise such as errors. also...
The resonator-induced phase (RIP) gate is an all-microwave multiqubit entangling that allows a high degree of flexibility in qubit frequencies, making it attractive for quantum operations large-scale architectures. We experimentally realize the RIP with four superconducting qubits three-dimensional circuit-QED architecture, demonstrating high-fidelity controlled-z (cz) gates between all possible pairs from two different 4-qubit devices pair subspaces. These are arranged within wide range...
Logic gates can be performed on data encoded in quantum code blocks such that errors introduced by faulty corrected. The important class of transversal acts bitwise between corresponding qubits and thus limits error propagation. If any gate could implemented using gates, the set would universal. We study structure <i xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">GF</i> (4)-additive codes prove no universal logic exists for these codes. This result...
Randomised benchmarking is a widely used experimental technique to characterise the average error of quantum operations. Benchmarking procedures that scale enable characterisation n-qubit circuits rely on efficient for manipulating those and, as such, have been limited subgroups Clifford group. However, universal computers require additional, non-Clifford gates approximate arbitrary unitary transformations. We define scalable randomised procedure over matrices correspond protected class...
Magic state distillation is one of the leading candidates for implementing universal fault-tolerant logical gates. However, circuits themselves are not fault-tolerant, so there additional cost to first implement encoded Clifford gates with negligible error. In this paper we present a scheme fault-tolerantly and directly prepare magic states using flag qubits. One these schemes uses single extra ancilla, even noisy We compare physical qubit gate protocol Meier, Eastin, Knill, which efficient...
Arbitrarily long quantum computations require memories that can be repeatedly measured without being corrupted. Here, we preserve the state of a memory, notably with additional use flagged error events. All events were extracted using fast, midcircuit measurements and resets physical qubits. Among decoders considered, introduce perfect matching decoder was calibrated from containing up to size-four correlated To compare decoders, used partial postselection scheme shown retain ten times more...
Compilers and computer-aided design tools are essential for fine-grained control of nanoscale quantum-mechanical systems. A proposed four-phase flow assists with computations by transforming a quantum algorithm from high-level language program into precisely scheduled physical actions.